In the electronics industry, and particularly in the computer industry, electrical signals are often transmitted between devices or components at a multiplicity of contact points. One example is a microprocessor having a large number of contact pins connected to corresponding contacts on, for instance, a printed circuit board within a computer. Typically, the microprocessor will have a pin grid array appropriately configured for mating engagement with corresponding contacts arranged in some type of socket or receptacle.
Generally, standard voltages are used to power various electrical components, such as microprocessors. For example, computers generally use a supply voltage of approximately 5.0 V to power various digital hardware devices. In certain applications, this can be problematic because heat is generated when current is supplied at 5.0 V. As electrical devices are continually downsized, such heat generation becomes a greater problem. In certain applications, microprocessors must be packaged in ceramic pin grid array packages which can withstand the heat. Cheaper plastic packages may melt or be otherwise damaged by excess heat. Ceramic packaging is more expensive to manufacture than plastic packaging, leading to increased cost of the finished product.
Certain electrical components are presently available which can be powered by 3.3 V, which creates substantially less heat than higher (e.g., 5.0 V) supply voltages. For example, certain microprocessor chips, such as the Am 486.TM. 3.3 V manufactured by Advanced Micro Devices, can be powered by 3.3 V and are available in plastic packages called plastic quad flat packages. The Am 486.TM. 3.3 V microprocessor chip is specially designed to allow the core microprocessor to operate at 3.3 V while providing compatible external signals of approximately 5.0 V. This allows the chip to function on about one-half the power of a conventional 5.0 V chip. Such chips or devices are also beneficial since the plastic quad flat package is a much narrower package than the conventional ceramic package. This is particularly advantageous when space is limited.
One problem, of course, is that many devices are powered by the standard 5.0 V power supply and 3.3 V components, such as 3.3 V microprocessors, cannot be used unless the power supply is converted from approximately 5.0 V to approximately 3.3 V. However, creating electrical signal conversion circuitry is generally costly and space consuming. Converting the electrical signal from one level to another is particularly difficult in tight spaces where there are multiple contacts, as with a microprocessor or other digital components.